There are a lot of things that I consider before investing in an ICO. I really think that the team that is responsible for the project has a great impact on the project it self. Active team development before and after ICO drives investors to invest more in a project. Marketing is another plus, usually people are enticed to invest the more they see an advertisement in social media and other sources. A great community also affects an ICO.
Nevertheless, all the crazy success stories make us look at the facts through rose-colored glasses. And the fact is that about 99% of all ICOs will fail. And this is not an exaggeration. Over the past few years, thousands of crypto-currencies have been created, and more than 90% of them failed. Another fact is that due to the success of the majority of ICOs, the market is flooded with scams, which create fake decentralized applications / coins to snatch off its piece from the ICO pie. In this way they successfully create an "ICO bubble". Be vigilant in choosing investment.